most of the times live cds, although we compiled them to provide high hardware support end up without supporting for some hardware ( its practically impossible to have drivers for all wireless cards in the market). so seems like the live cd doesnt have the support for your card however you can get it worked by installing the OS on your HDD and get the drivers setup.

@L3O, Sir I have installed matriux Leandros, it seems to not supporting wifi adapter in my Dell N5050 Laptop. the OS doesn't even detected my wifi card. I tried iwconfig command but it show no wireless adapter found. so where to download the driver for my wlan card? please help me.